- 2008 San Juan Islands
- 2010 San Juan Islands
- 2015-16 Puget Sound
- 2018 San Juan Islands
- 2018 Vector Survey (Strait of Georgia)
- 2018 Gulf Islands Survey
5/25/2021
The mean stratum density (\(\overline{D_s}\)) for a given taxon was the the sum of the individual transect densities divided by the number of transects (\(N_s\)):
\[ \overline{D_s} = \frac{\sum\limits_{i=1}^N D_i} {N_s} \] Total abundance (\(P\)) in numbers of individuals was the product of the stratum surface area (\(SA_s\)) and the mean taxon density (\(\overline{D_s}\)), with variance calculated as the product of the square of the surface area and the variance of mean stratum density:
\[ P_s = SA_s\overline{D_s};Var(P_s) = SA_s^2Var(\overline{D_s}) \]
| survey | area | year | abundance | CV |
|---|---|---|---|---|
| 2008 San Juan Islands | San Juan Islands | 2008 | 47,407 | 25 |
| 2010 San Juan Islands | San Juan Islands | 2010 | 114,494 | 33 |
| 2015-16 Puget Sound | Puget Sound Proper (excluding Hood Canal) | 2015, 2016 | 6,285 | 29 |
| 2015-16 Puget Sound | Hood Canal | 2015, 2016 | 14,699 | 23 |
| 2018 San Juan Islands | San Juan Islands | 2018 | 19,059 | 33 |
| 2018 Gulf Islands - High Stratum | Gulf Islands (Inside) | 2018 | 83,783 | 34 |
| 2018 Gulf Islands - Medium Stratum | Gulf Islands (Inside) | 2018 | 58,887 | 72 |
| 2018 Vector | Strait of Georgia (CA) | 2018 | 1,613,716 | 14 |